private final String vertexShaderCode =
	"attribute vec4 a_Position;" +
	"attribute vec4 a_Color;" +
	"attribute vec2 a_TexCoordinate;" +
	"varying vec3 v_Position;" +
	"varying vec4 v_Color;" +
	"varying vec2 v_TexCoordinate;" +
	"void main() {" +
	"v_Position = a_Position;" +
	"v_Color = a_Color;" +
	"v_TexCoordinate = a_TexCoordinate;" +
	"gl_Position = a_Position;" +
	"}";

private final String fragmentShaderCode =
	"precision mediump float;" +
	"uniform sampler2D u_Texture;" +
	"varying vec2 v_TexCoordinate;" +
	"void main()" +
	"{" +
		"gl_FragColor = texture2D(u_Texture, v_TexCoordinate);" +
	"}";

----------------------------

mProgram = GLES20.glCreateProgram();
checkGlError("glCreateProgram");
GLES20.glAttachShader(mProgram, vertexShader);
GLES20.glAttachShader(mProgram, fragmentShader);
/*
GLES20.glBindAttribLocation(mProgram, 0, "a_Position");
GLES20.glBindAttribLocation(mProgram, 1, "a_Color");
GLES20.glBindAttribLocation(mProgram, 2, "a_TexCoordinate");
*/
GLES20.glLinkProgram(mProgram);

FloatBuffer vertexByteBuffer = ByteBuffer.allocateDirect(vertices.length * 4).order(ByteOrder.nativeOrder()).asFloatBuffer();
vertexByteBuffer.put(vertices).position(0);

GLES20.glUseProgram(mProgram);

------------------------------

int mPositionHandle = GLES20.glGetAttribLocation(mProgram, "a_Position"); // ERROR! 0x501